Timeless appeal

Patek Philippe's perpetual calendar-chronograph timepieces of various vintages will instantly catch the eye of hard-core watch collectors, while the rest of us will be at a loss when the reference numbers are called as the auctioneer brings the hammer down to seal the final bid for a "hot" Patek Philippe watch.

The reference numbers that appear regularly at major watch auctions, especially when record prices are achieved, are 1518, 2499 and 5970. A check shows that they are the perpetual calendar-chronograph models Patek Philippe produced between 1941 and 2011.

These are arguably the world's most collectible watches, at least for investment, fetching millions of dollars in the market today. Last October, a rare pink-gold piece of the watches was sold for US$2.99 million at an auction.

No other watch has appeared on as many watch auction catalogue covers as the Patek Philippe perpetual calendar-chronograph - a timepiece that, once set, requires no more adjustments to tell the day, date and month correctly. At the same time, it's also used as a stopwatch.

"These timepieces have become icons of watch-investing and are now widely considered to be wearable works of art - the 'holy grail' for any collector of wristwatches," says a Christie's guidebook for collecting timepieces.

Why are they so popular? A perpetual calendar-chronograph takes engineering wizardry to combine two complicated functions, making the watch perhaps the most important pairing of complications. Stamp the Patek Philippe name on it, and it represents the highest quality in construction, craft and design.

Rolled out in 1941, Ref 1518 is Patek Philippe's first serially produced complicated watch. Powered by a Valjoux movement, it sets the basic design template for the brand's perpetual calendar-chronographs to come: an aperture at 12 o'clock on the dial; two sub-dials at nine and three o'clock; and a moon-phase at six.

The 35mm timepiece - with 281 pieces produced, mostly in yellow gold - is definitely a collector's favourite. Earlier, it had caught the attention of King Farouk of Egypt and American banker Henry Graves, known to be the 20th century's greatest watch collector.

The stainless steel version of Ref 1518 is considered the world's most precious and rarest watch, valued at over US$2 million. At 1,450 Swiss franc (S$1,992), it was half the price of the gold versions when it was rolled out during World War II. But only four steel pieces were made. In 2016, one of them was sold for US$11.13 million.

Ref 2499, a larger (36.2 and 37.7mm) model which followed after 1518 stopped production in 1950, is just as hot - in particular, the only two platinum watches in its collection. One is still kept by Patek Philippe, while the other was famously owned by Eric Clapton, who sold it in 2012 for US$3.6 million.

The pink-gold model is also sought-after. Christie's sold one for US$2.75 million in 2012, while another pink gold Ref 2499 had gone for US$2.16 million.

Production for 2499's successor, Ref 3970, jumped to 4,200 timepieces (from 349 for Ref 2499) - even though the model had a shorter production run, from 1986 to 2004. Its the first Patek Philippe perpetual calendar-chronograph to be produced in a modern factory - and it's given a new Lemania-based movement, housed in a smaller 36mm case. Probably because of the larger output, 3970 has not done as well as 1518 and 2499 at auctions.

Rarity is a key selling feature. Take Ref 5004T, which is essentially the same as the 3970 model, except that it sports a split-seconds chronograph - not just a chronograph - with a perpetual calendar; and it's a unique piece made of titanium. The watch went under the hammer for US$3.98 million at a charity auction in 2013.

Patek Philippe's current perpetual calendar-chronograph model is the Ref 5270, which is equipped with an in-house movement and has a 41mm case. It first appeared in white gold in 2011. A rose gold version was launched in 2013 and a platinum model appeared in 2018. These are also popular, but it's too early to gauge their true value. W